Two prominent technologies for telecommunications service providers are cable and digital subscriber line (DSL). Cable technology delivers broadband services typically through a coaxial medium called a cable network connected to a cable modem in the subscriber's home or office. DSL technology delivers broadband services typically through a twisted-pair telephone line medium connected to a DSL modem in the subscriber's home or office. DSL modems are available in various types classified based on the available upstream and downstream bandwidths. These classifications include symmetric DSL (SDSL) where the upstream and downstream bandwidths are equal, asymmetric DSL (ADSL) where the upstream and downstream bandwidths are not equal, high-bit-rate DSL (HDSL), very high bit rate DSL (VDSL), and others.
Historically, cable modems were shipped in “bridge mode” on a Dynamic Host Configuration Protocol (DHCP) network, and routers were shipped by default in “routed mode”, with network address translation (NAT) enabled, local area network (LAN) DHCP server enabled, and wide area network (WAN) DHCP client enabled. Typically, “bridge mode” indicates that devices on the LAN acquire (or are assigned) a public IP address from a DHCP server in the WAN, while “routed mode” indicates that devices on the LAN acquire (or are assigned) a private IP address from a local DHCP server on the LAN (the router would obtain a public IP address from a DHCP server in the WAN. This address would be shared by the LAN devices with Network Address Translation (NAT) between public and private IP domains performed by the router). This typically required no additional configuration for either LAN devices or the router from the end user in order to establish an Internet connection. Cable modem configuration defaults have been stable in the marketplace.
In contrast to the cable market, the DSL market has changed significantly over time. Historically, DSL modems were also shipped in “bridge mode”. However, the DSL network protocol was typically Point-to-Point Protocol over Ethernet (PPPoE) for IP address acquisition/assignment. Use of PPPoE required additional, manual configuration (typically username and password) of a LAN device or router from the end user. Since DSL modems were typically delivered with generic defaults (and in bridging mode), the user was typically required to change the default configuration of the LAN device or the router from a WAN DHCP client to a WAN PPPoE client, and to enter the PPPoE username and password so the LAN device or router could login to the network (i.e., be authenticated and subsequently acquire a public IP address). Since the username and password are unique to the individual DSL subscriber, it was not practical to ship devices, especially routers, in PPPoE mode by default. Furthermore, this manual configuration by the user was error prone and costly to a service provider or equipment supplier since many end users failed to properly configure the devices, requiring a technical support system to respond to configuration problems, thereby increasing the cost of supporting these subscribers.
While cable modems are standardized and certified so that configuration defaults may be assumed, there was previously no industry-wide certification process for a DSL modem, and no automated way to determine if a modem was compliant with a particular standard. Although standards exist, and it is reasonable to assume that future DSL modems manufactured for use with DSL service providers will likely be compliant with most if not all of the requirements from a relevant standard, compliance to these standards are not guaranteed. Accordingly, there is a need in the art for a discovery and identification system and apparatus for self-configuration of a CPE device.
Embodiments of the present invention and their advantages are best understood by referring to the detailed description that follows. It should be appreciated that like reference numerals are used to identify like elements illustrated in the figures.